B7100 throttle springs.

USMC8999

New member

Equipment
B7100D
Jul 26, 2023
22
1
3
Oklahoma
Could you please send me a picture of your spring setup at your throttle on a B7100D, or its a 750 engine. I want the best way and I hear there are several. Thankyou
 

Caden

Active member

Equipment
1979 B7100
Apr 16, 2026
205
102
43
Virginia
Foot throttle or hand throttle?

Mine is a HSE model, only has hand throttle. Can attach a pic if you want.
 

USMC8999

New member

Equipment
B7100D
Jul 26, 2023
22
1
3
Oklahoma
I am having trouble getting this adjusted properly. It was missing the throttle rod and springs. When I put this throttle rod on i can not figure out how to spring it so it operates properly. It seems when I try to adjust it that if I go to far it will go from max throttle to shutting it off?
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
35,771
10,825
113
Sandpoint, ID
Houston we have a problem!

What the heck is that spring doing on there?
It's not supposed to be there!
No wonder you cant get it adjusted its wrong!

If you have a B7100D and and not a B7100HST
This is the available 2 throttle levers:

1782669451459.png


This is the linkage:

1782669513772.png
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
35,771
10,825
113
Sandpoint, ID
Thank you for sharing. I have not seen one like that and I have had 2 of these
Put up some pictures of your full throttle contrrol linkage and I should be able tell you where the spring is supposed to go.
 

USMC8999

New member

Equipment
B7100D
Jul 26, 2023
22
1
3
Oklahoma
This is the top view from the hand throttle leaver going forward. The rod connects directly a lever to what the parts manual calls the ( lever,speed control)
My throttle rod or entire throttle linkage system has no springs anywhere. So when I press the floor pedal it will not return to idle once depressed or once the hand throttle. There is also no forward stop so when i puhs the hand throttle I can push past max throttle to a point that it will cut the tractor off, sounding like it is no longer in that sweet spot of cranking. So I have to pull it back down by hand. Springing it to keep in that operational sweetspot is my goal.
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
35,771
10,825
113
Sandpoint, ID
The return spring for the foot pedal is here:

1782755375951.png

The return spring for the stop lever is here:

1782755471683.png

If the throttle lever moves too easily and does not stay in one position then it needs adjusted or new spring washers installed.
To adjust tension on spring, unlock nuts 21, tighten the inside nut, then relock the nuts together.

1782755621408.png

As far as the engine dieing when being over throttled, that's this adjustment:

1782755742284.png

Low idle adjustment is set with this adjustment:
1782755855448.png
 

USMC8999

New member

Equipment
B7100D
Jul 26, 2023
22
1
3
Oklahoma
The return spring for the foot pedal is here:

View attachment 176439

The return spring for the stop lever is here:

View attachment 176440

If the throttle lever moves too easily and does not stay in one position then it needs adjusted or new spring washers installed.
To adjust tension on spring, unlock nuts 21, tighten the inside nut, then relock the nuts together.

View attachment 176441

As far as the engine dieing when being over throttled, that's this adjustment:

View attachment 176442

Low idle adjustment is set with this adjustment:
View attachment 176443
Sir,
I have addressed those and now I think think the issue may be in the box under the leaver in the first photo. The leaver that the throttle rod connects to. This morning I got the minimum and maximum rpm and was able to use the tractor for about 15 minutes but once it got hot it those earlier min and max rpm were no where close to where they were cold. Does this make any sense to you. Im no mechanic but im mechanically inclined and cant figure this one out.
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
35,771
10,825
113
Sandpoint, ID
The linkage should not change the RPMs as it runs.

Sounds like you might have an internal governor spring issue.
Or you have an injector issue.
Does it smoke?
Does it have blowby?

Take a video of it doing what your saying and post it on You tube and give us a link to see it.
 

Russell King

Well-known member
Lifetime Member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
7,734
2,999
113
Austin, Texas
The linkage should not change the RPMs as it runs.

Sounds like you might have an internal governor spring issue.
Or you have an injector issue.
Does it smoke?
Does it have blowby?

Take a video of it doing what your saying and post it on You tube and give us a link to see it.
Possibly there is some looseness at the hand throttle that could increase (or decrease) the engine speed as the tractor was used???

Look at the bottom of the hand accelerator diagram in post #14 third picture. NIW told you how to adjust that linkage if that is what you are describing.